This invention relates generally to the creation of visual effects, and more particularly to a three-dimensional image or "shot silk" effect created by an array of reflective facets with controlled slopes.
We live in a three dimensional world but for practical reasons choose to represent it primarily on two dimensional surfaces. Since the cave wall paintings made in prehistoric times man has tried to find ways to approximate three dimensions in two dimensional representations. Shading, perspective, and many other purely graphical techniques are early examples of these efforts. Stereopticons, 3-D photography, and holograms are more modern examples.
Viewers construct three-dimensional visual percepts from the two-dimensional image of the world projected onto the retina using many different cues: perspective, interposition, shadows, etc. (Rock, Irvin, 1975. An introduction to perception, New York: Macmillan). Several of the techniques which create the illusion of three dimensions in two-dimensional representations exploit the "parallax" cue, that is, the fact that when looking at a three-dimensional scene we see a slightly different view from the right and left eyes. (This is the so-called "binocular disparity"). Examples are stereopticons and 3-D photography which presents different scenes to the two eyes by various means. The parallax cue can also function monocularly (and does so for one-eyed individuals) if a different view is seen when the observer looks at the representation from a different angle as is possible, for example, with modern holograms.
The present invention exploits the parallax cues obtained from reflections or highlights, i.e., that in a three-dimensional scene the point within the scene from which a given incident light ray is reflected is different depending on the angle at which the scene is viewed. The viewer's experientially-based knowledge of how to reconstruct shapes from such reflections undoubtedly also comes into play to enhance the illusion.